研究了采用凝胶色谱法净化,HPLC-DAD同时快速测定食品中对位红和苏丹红Ⅰ-Ⅳ号染料的方法.样品经环已烷/乙酸乙酯(1+1)萃取,Bio-Beads SX3凝胶层析柱净化去除油脂、天然色素等大分子干扰物质.采用Zorbax SB-C18(4.6 mm×250 mm,5 μm) 色谱柱,以乙腈-乙酸水溶液(pH 4.0)为流动相梯度洗脱,二极管阵列检测器多波长同时检测染红食品中对位红和苏丹红Ⅰ-Ⅳ号染料.在0.1-10.0 mg·L-1浓度范围内,方法具有良好的线性关系(r＞0.999),样品的平均回收率为88.6%-99.2%,相对标准偏差为1.35%-3.57%,对位红和苏丹红Ⅰ-Ⅳ的检出限分别为1.8,5.0,9.5,8.0,6.5 μg·kg-1.

A study on the simultaneous determination of para red and sudan red dyes (in cluding sudan Ⅰ,Ⅱ,Ⅲ and Ⅳ) by HPLC with diode array detector after purification with gel permeation chromatography was reported in this paper.Samples were extracted directly with a mixture of cyclohexane-athylacetate (1+1) and purified by passing through a column packed with Bio-beads SX3 gel,to remove interfering high molecular fatty substances and natural colorants in food samples.Chromatographic column of Zorbax SB C18 (4.6 mm×250 mm,5 μm) was applied,and aqueous solution of acetonitrile,containing 3 drops of acetic acid (pH 4.0) was used as mobile phase in the gradient elution.Multiwavelength diode-array detection was applied in the determination of the 5 compounds mentioned above.Linear relationships in the range from 0.1 to 10 mg·L-1 of either of the 5 compounds were obtained with correlation coefficients (r) larger than 0.999.RSD′s obtained were in the range of 1.35% to 357%,and average recoveries were in the range of 88.6% to 99.2%.Detection limits were found to be 1.8 μg·kg-1,5.0 μg·kg-1,9.5 μg·kg-1,8.0 μg·kg-1 and 6.5 μg·kg-1 for para red,sudan Ⅰ,sudan Ⅱ,sudan Ⅲ and sudan Ⅳ respectively.